有些是人为的，有些则是自然发生的。

Some are man-made and others happen naturally.

youdao

自然发生的森林火灾甚至比山体滑坡或积雪更能促进白杨树的生长。

Even more than mountainside slides of mud or snow, naturally occurring forest fires promote the survival of aspen trees.

youdao

有一些变暖是自然发生的。随着上一个冰河时代的结束和冰的融化，我们已经经历了长达20，000年的变暖过程。

Part of the warming is natural; we have experienced a 20,000-year-long warming as the last ice age ended and the ice melted away.

youdao

The pasting back together occurs partly naturally by this process of hybridization, but hybridization only re-establishes the base pairing.

片段和载体的重新粘合一定程度上,是通过杂交自然发生的,但杂交只能重建碱基配对

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It is something that happens pretty much automatically, with a kind of fluidity that Mike has never achieved.

这是一个相当自然就发生的事情，其中的流度迈克从来没有实现过。

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For my perspective, even if you understand God to be the creator of the world, I don't think that means that God is causing a certain natural event to happen at certain time.

从我的角度来说，即使你明白,上帝是世界的创造者，但这并不意味着上帝,导致了某个自然界的现象在特定的时间发生。

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